Metallocene Combinations in Ethylene Polymerization: A Cyclic and Differential Pulse Voltammetry Study

Abstract

A series of metallocenes, namely [Cp 2 ZrCl 2 ], [(MeCp) 2 ZrCl 2 ], [(nBuCp) 2 ZrCl 2 ], [(iBucp) 2 ZrCl 2 ], [(tBuCp) 2 ZrCl 2 ] , [Cp 2 TiCl 2 ], [Et(Ind) 2 ZrCl 2 ], [Et(IndH 4 ) 2 ZrCl 2 ] and [Mesi 2 (Ind) 2 ZrCl 2 )], were combined in a 1:1 molar ratio within a reactor for ethylene polymerization, with MAO as the cocatalyst. The catalysts were characterized by cyclic and differential pulse voltammetry. The combined systems that showed the highest and lowest activities were combined in 1:3 and 3:1 molar ratios. The catalyst activity in the ethylene polymerization reaction is discussed in terms of the estimated consumption rate, decomposition rate constant and half-life of the metallocene species formed with MAO in an ethylene atmosphere.